How Did Houdini Trick Conan Doyle?

To demonstrate how spirit photographers could seemingly capture images of the dead interacting with the living, Houdini arranged to have himself photographed with the long-dead Abe Lincoln. (Credit: Library of Congress)

Eric Weisz, better known to the world as Harry Houdini, was born on this date in 1874. Famous for his feats as an escape artist and magician, Houdini also became one of the most crusading anti-spiritualists of the 1920s. Because of his familiarity with the illusions of stage magic and sleight of hand, Houdini was particularly adept at spotting the trickery that the so-called psychics and spirit mediums then hawking their services as conduits to the afterlife to the credulous grieving public commonly used. (Can you imagine anyone being foolish enough to fall for such predatory charlatanry today?)

That turn in Houdini’s career led him to collaborate with Scientific American on a lengthy exposé of spiritualism. Scientific American had offered a $5,000 reward to any medium who could satisfy its panel of investigators, which included Houdini, two of the magazine’s editors (J. Malcolm Bird and Austin C. Lescaboura) and others, that his or her paranormal gifts were genuine.

Unfortunately, although the magazine’s panel did reveal many frauds during the few years of its tenure, the whole episode ended very badly. The problem—which in retrospect is quite evident to anyone who has read through the Scientific American archives of that time, as I did—was that at least one of the editors, Malcolm Bird, was not so secretly a believer in the afterlife and very much wanted a psychic to succeed.

Matters came to a head in 1924 when the team was evaluating a psychic whom it called “Margery” in print, though we now know her to be Mina Crandon, the comely young wife of a Boston socialite and surgeon. You can read Houdini’s own account of the messy business that resulted, but in short: Mina Crandon’s seance tricks, perhaps aided by her personal charm, bamboozled Bird and the rest Scientific American group with the exception of Houdini, who was not initially at their meetings. They were prepared to award her the prize but Houdini protested that he needed to see for himself. At the seance, Houdini saw through the deception and called “Margery” on it, much to the annoyance of Bird, who angrily resisted exposing her con game. The arguments that followed led to the dissolution of the ghostbusting squad, and the $5,000 was never awarded.

What Houdini’s account does not say, but which I have heard as a perhaps unreliable rumor, is that the dispute between Houdini and Bird actually turned into a physical brawl. (Ahh, the two-fisted SciAm editors of yesteryear….) Also, when I attended James Randi’s The Amaz!ing Meeting in Las Vegas in 2003 and talked about these events, magician and mad debunker Penn Jillette told me that he had heard directly from Mina Cranston’s granddaughter that Mina had been sleeping with several members of the team, including Bird. (Oh, the scandal!) That just might help to account for Bird’s umbrage at Houdini’s harsh quashing of Mina’s scam.

But that is not the anti-spiritualist episode I would like to talk about today.

Rather, turn to a particular occasion when Houdini was trying to disabuse Sir Arthur Conan Doyle of his own spiritualist inclinations. Conan Doyle was not the paragon of rationality and reason that one might assume the creator of Sherlock Holmes would be: he had a soft spot for mediums. (It tends to make one think of Holmes’s famous dictum that “when you have eliminated the impossible, whatever remains, however improbable, must be the truth” in a somewhat different light.) Nevertheless, because Houdini and Conan Doyle had come to be friends, Houdini wanted to open the author’s eyes to the psychic frauds, and so he staged a demonstration that he hoped would do the trick.

In the spring of 1922 Conan Doyle visited Houdini in his New York City home, whereupon the magician set out to demonstrate that slate writing—a favorite method among mediums for receiving messages from the dead, who allegedly moved a piece of chalk across a slate—could be done by perfectly prosaic means. Houdini had Conan Doyle hang a slate from anywhere in the room so that it was free to swing in space. He presented the author with four cork balls, asking him to pick one and cut it open to prove that it had not been altered. He then had Conan Doyle pick another ball and dip it into a well of white ink. While it was soaking, Houdini asked his visitor to go down the street in any direction, take out a piece of paper and pencil, write a question or a sentence, put it back in his pocket and return to the house. Conan Doyle complied, scribbling, “Mene, mene, tekel, upharsin,” a riddle from the Bible’s book of Daniel, meaning, “It has been counted and counted, weighed and divided.”

How appropriate, for what happened next defied explanation, at least in Conan Doyle’s mind. Houdini had him scoop up the ink-soaked ball in a spoon and place it against the slate, where it momentarily stuck before slowly rolling across the face, spelling out “M,” “e,” “n,” “e,” and so forth until the entire phrase was completed, at which point the ball dropped to the ground.

Houdini then explained that he had done the whole thing through simple trickery and implored Conan Doyle to give up his spiritualist beliefs. Alas, he failed: not only did Conan Doyle continue to believe in mediums but he suspected that Houdini knowingly or unknowingly used his own supernatural gifts in the performance of his escape acts.

Here is my question for the hive mind: How did Houdini do it? Magicians are of course famously reluctant to reveal how they do their tricks, and it’s not clear that Houdini showed the secret to Conan Doyle. (Perhaps that’s why Conan Doyle refused to be convinced.) Rather than ask a magician to break his professional code, I thought I would ask you readers to suggest how Houdini accomplished his “ghostly” slate writing.

Here are my own uninformed guesses about elements of the trick, which still probably don’t quite cohere into a full explanation.

My sense is that the slate hung from wherever it was placed by wires attached to its four corners so that it could swing freely but also hang level. I suspect that a marionette-like arrangement of those wires could in theory allow a ball to be rolled across the slate’s surface as required.

Conan Doyle’s cutting into one of the cork balls to prove it had not been tampered with does not preclude his selected ball from being tampered with or replaced subsequently, when he is not looking.

Sending Conan Doyle down the street to write his secret message would give him a sense of privacy, but of course it also would allow Houdini (and unknown cronies?) a chance to reset the slate and the balls as they chose.

Any good pickpocket could probably remove that page with Conan Doyle’s message from his pocket, look at it and return it without him being the wiser.

That’s my best hypothesis about how Houdini did it. What’s yours?

Update (added 3/25, 8:23 a.m.): Via Twitter, P. Kerim Friedman tells me that these two books (here and here) may hold the answer, although those explanations aren’t immediately available online. So I’d still like to hear your theories.

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